Joyce Carol Oates is obsessed with that greatest of American themes - the quest to recreate the self. So obsessed is she, that she has written more than 100 books, many grappling with this goal. The 'tattooed girl' is a trademark character of her fiction; a young woman struggling to feel safe in her own skin, despite the scars of abuse lacerating her life. For Oates, it is love that recreates us, but love requires repositioning the precious boundaries of the self to let others into our charmed circle.

'How is intimacy accomplished?' ponders the fiercely reclusive writer, Joshua Seigl, a bachelor living in upstate New York and author of a successful novel about the Holocaust. He believes himself autonomous until, besieged by a degenerative 'nerve disease' he is forced to admit that he cannot live by books alone. Attracted by her strange sexual allure, he hires the near-illiterate young woman, Alma, as his assistant, for 'we require a stranger to complete us, where we lack the strength to complete ourselves'.

Alma is an inconclusive riddle, inviting but resisting translation. She is defined by the graffiti-like tattoos covering her body 'like a miniature language', injected by a gang of males who drugged and raped her. Seigl mistakenly interprets the moth-shaped tattoo on her cheek as a birthmark and suggests cosmetic surgery, blind to the fact that the abusive needles sank deeper than the skin's surface, puncturing her self-esteem, staining her psychological membrane.

Regarded as a freak, Alma is fuelled by a hatred burning 'like liquid flame in her veins' towards those who do not love her. She absorbs her abusive, anti-Semitic lover's prejudice against 'the rich Jew' Seigl, unaware that he isn't actually Jewish and of his growing affection for her. Alma mixes her employer's medication, sprinkles ground glass into his casserole, smears menstrual blood into the red wine sauce of beef stew, and plots ways to kill him.

Meanwhile, Seigl's 'leaky-valved heart' races faster and faster as his brain and body degenerate, but 'he'd taken for granted that, being an American born in 1964 of well-to-do parents, he was matter, and he mattered. Now, he understood that he was becoming anti-matter'. Whenever the proud Seigl starts to think he might matter again, he has a fall, stumbling in a cemetery, falling asleep at the wheel of his car and eventually slipping to his death.

The bloodstained monsters stalking through Oates's fiction are born from distorted conceptions of the self, whether as superhuman, like Siegl, or subhuman, like Alma. The greatest stumbling block against Seigl's writing is other people's vision of him as a failing genius, like facing a 'funhouse mirror'.

It is only under 'the roving eyes of strangers', though, that such strangeness can be made familiar, humanised. Seigl is a 'parenthetical man', almost hermetically sealed from the world, but Oates traces the fingerprints that seep into even the most thick-skinned of people as Alma's 'touch' sparks a mutual love. In the writer-assistant relationship, Oates examines the impulse to make a mark on life and the desperate need - yet fear - of somebody to witness to our existence, to 'translate' us accurately.

The Tattooed Girl is as startlingly sharp as it is tender, cutting through taboos of physical and sexual abuse so that the pain of the inarticulate is given a voice so piercingly real it prickles the blood. As Alma and Seigl struggle to comprehend an increasingly slippery world, Oates punctures her language and infuses it with extreme sensuousness in a somewhat irritating adjectival overload. The novel is soaked in the menacing atmosphere of a feverish nightmare, a hell on earth, in which the beating, porous heart is a timebomb.

Oates refuses, though, to offer any conclusiveness: she peers through the eye of the needle, but never passes through. She revels in pointlessness, circling repetitiously around her point, but never landing.

'Amid such debris it requires a sharp yet patient eye to discern treasure,' writes Oates of Alma, who floats up to New York from rural Pennsylvania. We must keep re-viewing seemingly fixed points and judgments, Oates seems to suggest, if we are to sift the worth from the waste and wreckage of a life, if we are to spot the lethal needle hiding in the haystack of prejudice.